A selective call radio frequency (RF) communication device (105) includes a receiver (203) for receiving and converting an RF signal into a converted signal. A controller (206) generates binary message information, a synchronization command signal and an address detection signal. An alert device (207)...http://www.google.de/patents/US5457716?utm_source=gb-gplus-sharePatent US5457716 - Automatic frequency control in a radio communication receiver
